A Redundant Arrays of Inexpensive Disks (RAID) device records a large amount of data handled by a computer system. For example, a RAID 5 protects data with a cost-effective and simple configuration. A RAID 6 that demonstrates higher reliability than the RAID 5 is also used.
Related techniques are discussed in Japanese Laid-Open Patent Publication No. 2007-87094, Japanese Laid-Open Patent Publication No. 7-311659, Japanese Laid-Open Patent Publication No. 7-110788, and Japanese Laid-Open Patent Publication No. 2006-163474.